MFH: r540716 r540718 r540719

security/putty*: upgrade to 0.74 security fix release

Changelog:
https://www.chiark.greenend.org.uk/~sgtatham/putty/changes.html

among them are these two---and more bugfixes beyond not listed here:

• Security fix: if an SSH server accepted an offer of a public key and then rejected the signature, PuTTY could access freed memory, if the key had come from an SSH agent.
• Security feature: new config option to disable PuTTY's dynamic host key preference policy, if you prefer to avoid giving away to eavesdroppers which hosts you have stored keys for.

Security: 6190c0cd-b945-11ea-9401-2dcf562daa69
Security: CVE-2020-14002
Security: FZI-2020-5

security/putty*: rename and update LICENCE from tarball.

Approved by: ports-secteam (joneum@) [540716]
Approved by: ports-secteam (blanket, metadata update) [540718, 540719]